Radiology Coding Alert

Question: When am I supposed to apply code Z98.1 (Arthrodesis status) on spinal exams? On one report, the physician states that the patient has had a “prior anterior cervical discectomy and fusion from C3-C5.” Would this qualify for use of Z98.1?

Michigan Subscriber

Answer: There’s certainly some confusion among coders as to when to apply Z98.1. Some believe it’s only supposed to be added as a diagnosis when the patient is in the post-op period of an arthrodesis. However, this code should actually be applied in all instances where a prior fusion or arthrodesis is documented.

Using the index, this code can be found via a few different routes. The most practical method is to simply search the index directly for “Arthrodesis status”. However, this doesn’t necessarily answer the question of what particular instances Z98.1 should be applied. Searching further, we find Z98.1 under both “Fusion” and “Status (post)”. Next to Status (post) à Arthrodesis, we see that Z98.1 can also be found by indexing “Presence (of).” Codes falling under Presence (of) are not subjected to any sort of surgical timeframe — but rather simply whether they are anatomically present. With this finding, we can make the confident determination that Z98.1 should be billed in cases documenting a history of arthrodesis.

Remember: Apply Z98.1 to all documented cases of arthrodesis, not just those involving the spine.